In the previous post I spoke about how a Virtual Application feature introduced in Workload Deployer v3.1 actually had benefits for Virtual System patterns as well. In that case I was talking about the ability to deploy Virtual Applications running on AIX to PowerVM hypervisors and how this had hidden benefits for Virtual Systems as well. This is a great example of how an enhancement to Virtual Applications can sometimes benefit Virtual Systems. However, this is not the only instance where the two pattern types intersect.

Several other new or enhanced features that are primarily for Virtual Applications are also being extended to benefit and improve Virtual Systems ... and vice-versa. One such area of improvement involves Shared Service in v3.1. These services were introduced in v3.0 specifically for the benefit of Virtual Applications. However, several enhancements have extended these capabilities to Virtual Systems and likewise, some functionality that was previously only available to Virtual Systems has been extended to Virtual Applications in the form of Shared Services.

As you may already know, Shared Services were first introduced in v3.0 and are just what the name implies; services that are deployed by a cloud administrator and used by multiple virtual application deployments. Let's start by taking a look at the shared services available under Cloud -> Shared Services in v3.1. You will notice that there are now more shared services listed than there were in v3.0.

In addition to the familiar Caching Service and ELB Proxy Service (formerly Proxy Service) there are now additional entries for an External Caching Service and an External Application Monitoring Service. For simplicity let's just start from the top and go down the list, discussing the function of each service, what is new/improved for v3.1 with regard to virtual applications, and when applicable how this service can be used by virtual systems.

Caching Service

The Caching Service was introduced in v3.0. Its primary purpose is to cache HTTP session data using a highly scalable and fast in-memory cache. This is the same core technology that is included in our WebSphere eXtreme Scale and DataPower XC10 Caching appliance. To make use of this service all you need to do is deploy an instance of the Caching Service with the configuration parameters of your choice into a cloud group where you want to leverage that service. As you create virtual application patterns you simply select the Enable session caching check-box when you add a scaling policy. When this pattern is deployed it will be automatically configured to leverage the Caching Service for session persistence. It's as simple as that.

Several new features were introduced in v3.1 for the Caching Service. First, the Caching Service can now be launched with parameters to define the behavior for automatic scaling to meet the ever changing demands of your applications. Once set, Workload Deployer will manage this service to ensure sufficient capacity based upon your requirements, adding or removing containers. Second, and this is significant for Virtual System patterns, the caching service has been enhanced to add new operations to support listing, creating, and deleting various types of object grids. You can then use the WebSphere eXtreme Scale ObjectGrid APIs to persist and manage content in the grid from your application code from Virtual System deployments. This saves you the trouble of creating and configuring your own caching service for these purposes outside of the cloud and permits sharing of the service you have already configured - a nice savings.

Caching Service (External)

The External Caching Service is one of the new additions for v3.1. Let's say that you already have configured a caching solution for your enterprise using the DataPower XC10 appliance or a collective of appliances. It would be nice if you could leverage this same solution instead of launching yet another caching solution within your private cloud. Leveraging your existing solution would consolidate your caching needs and preserve the cloud resources for other purposes. With this new external caching service you can do just that. It provides you the ability to leverage an external caching solution for both your Virtual Application session persistence needs as well as your Virtual System and even non-cloud caching needs. Just point an instance of this external caching service at your DataPower XC10 caching solution and all of the HTTP session persistence needed by your virtual applications in the same cloud group will make use of the external caching service. You can also point multiple instances of the external caching service in multiple cloud groups to share the same XC10 appliance or collective.

Monitoring Application (External)

With the External Monitoring Application service you can deploy an External Application Monitoring service reference within a cloud group to point at a Tivoli Enterprise Monitoring Server installation outside of the cloud. The TEMS server must be at version 6.2.2 Fix Pack 5 or later. Once created, the Unix or Linux OS monitoring agents and the Workload monitoring agent that is provided for virtual application workloads will be automatically connected to the defined instance of the Tivoli server using the supplied primary and fail-over Tivoli Enterprise Management server, protocol, and port. This is especially useful if you want to consolidate all of your monitoring to a common console. As with the External Caching Solution, this enhancement also extends the integration capabilities of Virtual Application Patterns beyond the scope of your private cloud and allows you to consolidate and leverage investments you have already made.

ELB Proxy Service

The Proxy Service was first introduced in v3.0 and renamed to the ELB Proxy Service in v3.1 for clarity. As the name implies, its primary purpose is to provide routing and load balancing to multiple deployed web applications. As with the caching service, you deploy this service based upon your requirements for load and availability within a cloud group. When defining virtual application patterns to leverage this service you simply add a routing policy and define your virtual host name. When the virtual application pattern instance is deployed to the cloud group the necessary configuration will performed to add the virtual host name and configure your application environment to use the ELB Proxy Service. New in v3.1 is the capability to scale the ELB Proxy Service itself to meet the changing demands of your application mix.

One other item that I should point out (and to which I've already alluded) is that you can now deploy multiple instances of each of the shared services - one per cloud group. Shared services can also now be deployed using environment profiles. This was not previously the case in v3.0 where each service was a singleton for the appliance. Allowing multiple instances of shared services gives you the flexibility to configure the sharing of your services as necessary for your particular environment.

I hope this post has provided a useful overview of the value of shared services and the new capabilities introduced in v3.1. I also hope that you can see how these services make it easier to implement your solutions for both virtual applications and virtual systems within a private cloud environment and shed a little light on how we are continuing to improve IBM Workload Deployer. As always, these improvements are driven by the feedback we receive from you so please let us know what you think!

When IBM Workload Deployer v3.0 rolled around, the appliance introduced the concept of shared services. These were services that a cloud administrator could launch into the cloud infrastructure defined to IBM Workload Deployer, and use to serve a number of different application deployments. There were, and continue to be, two main shared services: a proxy service and a cache service. The shared proxy service does pretty much what you may guess. It provides request routing capabilities across multiple different instances of multiple different applications, thereby providing a centralized resource that encapsulates this basic need in an application environment. You can probably also guess what the caching service does. It caches things! Specifically, in IBM Workload Deployer v3.0 it provided in-memory caching of HTTP sessions, thus ensuring high availability of data stored in those sessions.

Undoubtedly, the ability to make HTTP session data fault tolerant is extremely critical in any application environment, cloud-based environments included. However, the applicability of a shared cache service is much further reaching, and in IBM Workload Deployer v3.1, we are starting to open this service up to your applications. What does this mean to you? Quite simply it now means that you can access this cache directly from your application code. If you are familiar with WebSphere eXtreme Scale or the DataPower XC10 Caching Appliance, then you know exactly what I mean. You can use the WebSphere eXtreme Scale ObjectGrid API to insert, read, update, and delete entries that exist in the in-memory cache. The underlying cache technology is based on the same code that powers WebSphere eXtreme Scale and DataPower XC10, so you can be sure that your cache is scalable, fault tolerant, responsive, and otherwise able to meet the needs of your application.

As I hope you find to be the case with many IBM Workload Deployer capabilities, this is a superbly simple capability to leverage. When you deploy virtual application patterns based on the IBM Workload Deployer Pattern for Web Applications, the capability is simply there. The underlying runtime that is serving your application is automatically augmented with the capabilities necessary so that your applications can connect to and utilize the deployed caching service. It is also worth pointing out that you can utilize the caching capabilities provided by this shared service for applications and application infrastructure that you deploy via virtual system patterns as well. You can either choose to augment the WebSphere Application Server environment with the XC10 Feature Pack (a deploy-time option for virtual system patterns built on WebSphere Application Server Hypervisor Edition v8), or you can configure WebSphere Application Server as you always would when integrating with a WebSphere eXtreme Scale environment or a DataPower XC10 Appliance.

What's the real benefit to all of this you ask? Well, when you use the shared caching service, you get the benefits of a distributed, in-memory, extremely scalable cache without having to deal with too much setup or administration. You simply tell IBM Workload Deployer how many resources you want to dedicate to your cache, and deploy the shared service. IBM Workload Deployer takes care of the details, including scaling in and out the cache to meet the needs of the system. On top of all of this, there is also an option to configure 'Next to the Cloud' caching. If you currently own DataPower XC10 appliances, you can make those available to virtual application pattern deployments (this was already possible with virtual system patterns) by simply providing details of the location of the appliance collective in question.

Put simply, setting up, administering, and utilizing an object caching service for your applications has never been easier. Check it out and let us know what you think!